Technical Field
The present invention relates to the design of the rear edge of a rotor blade of a wind turbine. The present invention furthermore relates to a spike-shaped rear edge, also referred to as rear edge ridge. The present invention moreover relates to a wind turbine rotor blade and method for mounting a rear edge ridge to a rotor blade. The present invention moreover relates to a wind turbine with rotor blades having at least one rear edge ridge.
Description of the Related Art
From EP 0 653 367 A1 we know that the rear edge should be saw-tooth shaped in a longitudinal direction of the main spar of the rotor blade, in order to reduce the noise level.
From EP 1 019 632 we know that the degree of tapering of the rotor blade in a transverse direction of the main spar of the rotor blade increases with increasing approximation to the rear edge, again in order to reduce the noise level.
From EP 1 314 885 B1 we know that the rear edge should be saw-tooth shaped in a longitudinal direction of the main spar of the rotor blade and, at the same time, flexible, in order to increase the torque that the rotor blade exerts on the generator.
From European patent application EP 0 652 367 A1 we know to provide a saw-toothed rear edge at a rotor blade, which is, for example, fixed onto a chamfered part of the rotor blade as a saw-tooth shaped strip 9.
As a matter of fact, practically no wind turbines with rotors blades with spike-shaped rear edges have been installed so far, although for example Document EP 0 652 367 stems from the year 1994. One reason might be that it is difficult to realize this in practice. The problems that need to be considered are associated, in particular, with costs, quality and durability. Also, it may be problematic to retrofit the rear edge ridges of rotor blades of already installed turbines or, at least, of already existing rotor blades.